release/src-rt-6.x/linux/linux-2.6/arch/mips/math-emu/sp_simple.c

   1 /* IEEE754 floating point arithmetic
   2  * single precision
   3  */
   4 /*
   5  * MIPS floating point support
   6  * Copyright (C) 1994-2000 Algorithmics Ltd.
   7  * http://www.algor.co.uk
   8  *
   9  * ########################################################################
  10  *
  11  *  This program is free software; you can distribute it and/or modify it
  12  *  under the terms of the GNU General Public License (Version 2) as
  13  *  published by the Free Software Foundation.
  14  *
  15  *  This program is distributed in the hope it will be useful, but WITHOUT
  16  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  17  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  18  *  for more details.
  19  *
  20  *  You should have received a copy of the GNU General Public License along
  21  *  with this program; if not, write to the Free Software Foundation, Inc.,
  22  *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
  23  *
  24  * ########################################################################
  25  */
  26
  27
  28 #include "ieee754sp.h"
  29
  30 int ieee754sp_finite(ieee754sp x)
  31 {
  32         return SPBEXP(x) != SP_EMAX + 1 + SP_EBIAS;
  33 }
  34
  35 ieee754sp ieee754sp_copysign(ieee754sp x, ieee754sp y)
  36 {
  37         CLEARCX;
  38         SPSIGN(x) = SPSIGN(y);
  39         return x;
  40 }
  41
  42
  43 ieee754sp ieee754sp_neg(ieee754sp x)
  44 {
  45         COMPXSP;
  46
  47         EXPLODEXSP;
  48         CLEARCX;
  49         FLUSHXSP;
  50
  51         /*
  52          * Invert the sign ALWAYS to prevent an endless recursion on
  53          * pow() in libc.
  54          */
  55         /* quick fix up */
  56         SPSIGN(x) ^= 1;
  57
  58         if (xc == IEEE754_CLASS_SNAN) {
  59                 ieee754sp y = ieee754sp_indef();
  60                 SETCX(IEEE754_INVALID_OPERATION);
  61                 SPSIGN(y) = SPSIGN(x);
  62                 return ieee754sp_nanxcpt(y, "neg");
  63         }
  64
  65         return x;
  66 }
  67
  68
  69 ieee754sp ieee754sp_abs(ieee754sp x)
  70 {
  71         COMPXSP;
  72
  73         EXPLODEXSP;
  74         CLEARCX;
  75         FLUSHXSP;
  76
  77         /* Clear sign ALWAYS, irrespective of NaN */
  78         SPSIGN(x) = 0;
  79
  80         if (xc == IEEE754_CLASS_SNAN) {
  81                 SETCX(IEEE754_INVALID_OPERATION);
  82                 return ieee754sp_nanxcpt(ieee754sp_indef(), "abs");
  83         }
  84
  85         return x;
  86 }